The Design Of Digital Single-phase Sine Switching Inverter

Power supply is core and drive of electric equipments. With the flying development of power electronics technology, It has come forth continually that is IC of high intelligence, new type electronic device and topology since 1990's. As a result, A lot of new type steady-voltage power supply has been created. High-frequency switching power supply is a branch of power supply. It possesses many advantages such as low-power, high-frequency, small- volume, light-weight, wide-range of steady voltage, credibility and security. It has been received and upheld by the people. It involves a great deal content that is extensive and intricate. It bestrides subject of three aspects. The first is IC control chip system of micro-electronics; The second is electronic devices of high-performance power semiconductor such as MOSFET and IGBT. The third is various devices of inductance and magnetic materials of transformer how to be utilized and rolled rationally.Steady voltage power supply of modern switching has been applied in the following aspects widely. They are DC power supply, AC power supply, industry power supply, computer power supply, UPS power supply, power supply of medical treatment and lighting, high voltage power supply of radar, power supply of sound and video frequency and so on. Single-phase Sinusoidal Pulse Width Modulation Inverter Power Supply in this paper belongs to AC power supply(AC-DC-AC convert). Control mode adopts two close loop feedback of voltage and current control. The methods of digital PI control method can change pulse width of drive voltage that adjust and rectify output voltage ultimately. The main circuit is made up of compounding of Buck and the full-bridge circuit. The control circuit adopts TI Company's product of TMS320LF2407 which is an excellent digital signal processing chip. It generates PWM waveform, SPWM waveform; provides the function of AD sampled and close loop control. Integrated DSP chip is more simple, reliable and laboratorial than discrete component. The operation of inverter power supply is thoroughly analyzed and some important formulas are deduced.Finally, the principle of operation are illustrated and verified on emulation and experimental results.